Petrified Wood (Silicified Wood)
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
mineral
Category
Organic (Often Found By Beachcombers)
Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.
Chert (or Flint)
Chert (Sedimentary Cryptocrystalline Sio2)
sedimentary
Fossiliferous Limestone (Crinoidal)
Calcium Carbonate (CaCO3) - Limestone containing bioclasts
sedimentary
Chert (Green variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (specifically a stream-worn Chert Nodule)
Sedimentary Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (specifically Red Chert or Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Amber
Succinite (specifically for Baltic Amber), Formula: C10H16O
Organic Gemstone (often associated with Sedimentary sequences)
Chert (specifically Flint or Gray Chert)
Silicon Dioxide (SiO2)
sedimentary
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
metamorphic
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Chert (often called Flint or Jasper depending on color)
Chert (SiO2 - Microcrystalline or Cryptocrystalline Quartz)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Petrified Wood
Silicified Wood (primarily SiO₂ / Silicon Dioxide)
mineral
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Fossiliferous Brachiopod in Shale
Brachiopoda (Phylum) preserved in Carbonaceous Shale
sedimentary
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Amber
Succinite (Fossilized Resin)
mineral
Yellow Chert (Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Freshwater Pearl
Aragonite / Biogenic Calcium Carbonate (CaCO3)
mineral
Chert (specifically Jasper or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Bituminous Coal
Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)
sedimentary
Anthracite Coal
Anthracite (Carbon-based organic sedimentary rock transitioned to metamorphic)
metamorphic
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Picture Jasper
Silicon Dioxide (SiO2) - Opaque Chert/Quartzite variety
sedimentary
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
mineral (silicate-replaced organic material)
Massive Cryptocrystalline Quartz (Chert/Chalcedony Pebble)
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
sedimentary
Pearl (incorporated into jewelry)
Aragonite and Calcite (CaCO3)
mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Chert (Iron-stained)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Iron-stained River Cobble)
Microcrystalline Quartz (SiO2)
sedimentary
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Brown Variety)
Silicon dioxide (SiO2)
sedimentary
Chert (Jasper-bearing)
Chert (Silicon Dioxide, SiO2)
sedimentary
Chert (Pebble)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Pearl
Calcium Carbonate (CaCO3) + Conchiolin
mineral
Chert (variant Flint/Jasper)
Microcrystalline Opaline Silica (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
metamorphic